高氮奥氏体不锈钢氩弧焊的重熔特征

焊接性是影响高氮奥氏体不锈钢(高氮钢)应用的一个重要因素.为了研究高氮钢的焊接特性,对此钢进行氩弧焊重熔试验,分析了熔融时间对焊缝特性的影响.试验结果表明,随着熔融时间的增加,焊缝中铁素体的含量增加.同时发现焊缝中存在热裂纹、气孔等焊接缺陷.低熔点硫化物共晶相是焊缝具有较强裂纹敏感性的主要原因.熔融时间显著影响焊缝中气孔的形成.

Remelting characteristics of high nitrogen austenitic stainless steel after GTAW

Weldability is one of the important properties that will be affected the application of high nitrogen austenitic stainless steel. In order to investigate welding characteristics of high nitrogen austenitic stainless steel, the remelting experiment after GTAW was conducted on the steel, and the influences of fusion time on the characteristics of the weld were discussed. Experimental results indicate that the percentage of ferrite in the weld metal decreased with the increase of the fusion time and this is attributed to the loss of nitrogen, which is a strong austenite-stabilizing element. It is also found that there are solidification defects, gas pores and hot cracking in the weld. Low-melting point sulfide eu-tectic is responsible for the hot cracking susceptibility and gas pore formation is sensitive to the fusion time.